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Zero charge rate in the cold

I took delivery of my Model S last Tuesday, I drove it to work Tuesday & Wednesday. Wednesday evening when I got home from work I parked outside & plugged the car in to a 110v outlet. Thursday I woke up to a big snowfall so I drove the SUV to work (no snow tires on the S yet). Checking the iPhone app it was saying I was getting 0 km/hr of charging which I assumed to be a bug or communication problem with the app. Unfortunately when I got home Thursday evening I found this was indeed correct, the car itself was showing 0 km/hr of charging & in fact the battery had lost 2 km of range despite being plugged in for almost 24 hours. It was cold that day, -14°C (7°F), but not extreme. It took until mid-Friday for the car to start accumulating 'distance' and the car's still plugged in now, Sunday evening, still trickling along at 2km/hr. In an e-mail with someone from Tesla I was told "110v is just enough to keep the battery warm", a very different message than what Tesla is publicly advertising:

Below is a picture from Thursday evening after the car had been plugged in for almost 24 hours. You can see the charge rate as well as the exterior temperature. I was a bit surprised to find that the battery took so long to warm up on 110v, especially after it had been parked indoors in a heated garage at work. If it truly does take a full day for the battery to achieve some internal temperature then that feedback should be provided on-screen or on the app. For the car to sit there for a full day appearing to do nothing is pretty disconcerting. The effects of temperature on charging need to be clearly communicated so there aren't any surprises when it comes to trip planning.

Yes, that's pretty well-known for us Northern Model S drivers. When you get somewhere in the vicinity of -15C to -20C the pack heater doesn't have enough power at 1.2 kW to raise the pack temperature enough to charge. If the car is outdoors additional heat loss due to wind can also be a factor.

IIt was cold that day, -14°C (7°F), but not extreme. It took until mid-Friday for the car to start accumulating 'distance' and the car's still plugged in now, Sunday evening, still trickling along at 2km/hr. In an e-mail with someone from Tesla I was told "110v is just enough to keep the battery warm", a very different message than what Tesla is publicly advertising:

The Tesla tool assumes room temperature and no battery warming load. Lithium batteries can not charge below 0 degrees Celsius, so the car must warm the battery to at least that before charging starts. Depending on how much cold soak there is (what is the starting battery temperature) this may take a while. If the ambient temperature is also lower than the minimum charging temperature, it only makes matters worse because the battery heater not only has to heat the battery but also has to constantly replace the heat that is being lost to the ambient temperature.

Given the car charges at 8km/hr with no warming load and it's charging at 2km/hr in your conditions, it's using 75% (990W) of the power just to keep the pack at charging temperature, 25% (330W) to charging. This also means under those conditions it will take 4x as long to warm the battery compared to if you parked the car in a garage at the charging temperature.

When you get somewhere in the vicinity of -15C to -20C the pack heater doesn't have enough power at 1.2 kW to raise the pack temperature enough to charge.

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Interesting. I was annoyed because the car's parked indoors all day at work (+16°C according to the car) and it was only a 10 minute drive home. I didn't think that would be enough to chill the battery but when I got home it already wouldn't accumulate a charge. Equally confusing was that Friday was similarly cold yet that was the day is started accumulating charge. It's in my driveway so it's pretty protected from the wind, especially with all the snow I've shovelled off the driveway onto the sides...

Given the car charges at 8km/hr with no warming load and it's charging at 2km/hr in your conditions, it's using 75% (990W) of the power just to keep the pack at charging temperature, 25% (330W) to charging.

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This is exactly the sort of information I would like to see publicized straight from Tesla instead of having to discover it empirically. The car tells you a fair bit of information about how it's consuming energy, I feel it should be equally explicit with how well it's receiving energy as well. Sure you can guess by looking at the numbers and at what the environment's like, but it's still a guess.

I experienced the same. When parked at a friends place within temperature below -10 C and plugged on a 110V outlet, the car barely maintain the rated range, but doesn't get any improvement.

I made an experiment which gives me an interesting result, but needs to be validated.
I parked the car within a - 12 C temp, and plug it to a 110 V for 6 hours and the temp was - 14 C when I left.
Using the phone apps, I warm the inside of the car in order to maintain a inside temp between +7 C and + 10 C (which is about +5 in "real" temp)
So about every 30 min I turn the climate on, for about 5 min, and then off... doing so, I was able to get a range increase about a little bit less than 2 km per hours (I got +10 km in 6 hours).

How can we make it clear to newbies to avoid the TM website and read the TMC?? TMC has the real goods whereas TM is not necessarily written by persons with any real world experience, i.e. beyond Sillycon Valley. Plus, who can actually read any of that tasteful pastel phantom text that has infected their entire website!?

I will give TM props that they DO promote getting a HPWC unit for your home garage, even suggesting ordering it way before delivery of the car. AMEN to that!! This is not just a hustle but a real helpful suggestion, esp in higher elevations & cold climates. Model_S *requires* at least 240 volts @ 30 amps charger at home! Repeat, rinse, repeat.
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Unfortunately, it's just the way it is with normal household power distribution, especially in US/Canada/Japan with our lower voltage systems. Rules dictate that short of a special receptacle (and I include 20A in these), the maximum intermittent load you can place on a circuit is 1850W (125V @ 15A) and the maximum continuous load you can place on a circuit is 1500W (125V @ 12A). You're running at 117V, so you get only 1400W to start with. By the time you add up charger efficiency losses and vampire loads, you're looking at only 1160W or so available to the car for charging. This means in *perfect* weather, you're looking at 73 hours to charge. Now bring in the weather - resistive heating is likely going to consume 1/2 to 3/4 of that, or more, to keep the battery pack near 0 deg C. So by the time you get done, you're looking at times that range from 5-8 days just to recharge the car from 0 in those conditions.

I'd like Tesla to consider making a NEMA 5-20 adapter available so that power could be boosted to 16A on 120V systems. That additional ~500W or so would make a big difference in these conditions, and many garages have 20A receptacle circuits already.

Plugged my cold soaked car (-2 C) to our Volt charger at work (15 amps @ 197 volts) and watched it sit at 0 mi/hr for about an hour, yet the rated range was creeping up. I assume this was the battery warming. It's now getting 2 mi/hr.

might also want to change from 'rated' to 'ideal' in the settings menu.

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I think the consensus around here was that "rated" range was more realistic than "ideal" and so that's why I typically leave it there. In the winter, I doubt I'm even getting "rated" and wouldn't want to be misled with an overly optimistic "ideal" number on the dash.

I think the consensus around here was that "rated" range was more realistic than "ideal" and so that's why I typically leave it there. In the winter, I doubt I'm even getting "rated" and wouldn't want to be misled with an overly optimistic "ideal" number on the dash.

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Yeah getting rated in these parts during the winter is nearly impossible if you are on the highway.

I was trailing a semi somewhat close for 30km on the 403 doing 104km/h last Thursday and couldn't get rated Wh/km!

I've been holding off adding this because it won't help, BUT . . . at -14C we would consider 108km a fat full charge, in the LEAF.
Different perspective. It will charge on 110 when it's icy cold tho! (Takes a while.) ML

I'd like Tesla to consider making a NEMA 5-20 adapter available so that power could be boosted to 16A on 120V systems. That additional ~500W or so would make a big difference in these conditions, and many garages have 20A receptacle circuits already.

Unfortunately, it's just the way it is with normal household power distribution, especially in US/Canada/Japan with our lower voltage systems. Rules dictate that short of a special receptacle (and I include 20A in these), the maximum intermittent load you can place on a circuit is 1850W (125V @ 15A) and the maximum continuous load you can place on a circuit is 1500W (125V @ 12A). You're running at 117V, so you get only 1400W to start with. By the time you add up charger efficiency losses and vampire loads, you're looking at only 1160W or so available to the car for charging. This means in *perfect* weather, you're looking at 73 hours to charge. Now bring in the weather - resistive heating is likely going to consume 1/2 to 3/4 of that, or more, to keep the battery pack near 0 deg C. So by the time you get done, you're looking at times that range from 5-8 days just to recharge the car from 0 in those conditions.

I'd like Tesla to consider making a NEMA 5-20 adapter available so that power could be boosted to 16A on 120V systems. That additional ~500W or so would make a big difference in these conditions, and many garages have 20A receptacle circuits already.

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I'd love a NEMA 5-20 adapter. They have one for the Roadster, so here's hoping we see one for the Model S at some point.

I'm doing just fine with 120V charging, but an extra 500W would be great. There's an outlet in my garage conveniently located exactly by the charger door with a direct run to the service panel on 12 gauge romex. It would be super simple to upgrade the breaker to 20A and swap out the NEMA 5-15 outlet for a NEMA 5-20.

The UMC uses the resistance of the pilot pin to the ground in the adaptor to determine the charge allowable. By adding a resistor to this value one can fool the UMC to charge at a rate larger than that is safe:wink:. As a test only! I dropped a 47Kohm resistor across the 2 pins (sunk it down with a Dremel) and attached it with a little super glue. The resistor is 1/8 w with thin leads that just rest in the pin receivers. The UMC can now charge at 20A (more than can safely be pulled off a 20A 110V receptacle). A different resistor will probably set it at 16A which is safe of a dedicated 20A circuit. For now I just dial down the value in the car.